Replacing animal fats with vegetable oils, a mainstay of modern health advice, may lead to an increased risk of death among people with heart disease, according to an analysis of data gathered 40 years ago. In a study of 458 men, those who had experienced a heart attack or other coronary event and replaced saturated fats with omega-6 polyunsaturated fats found in corn, sunflower and safflower oil had a 16 percent rate of death from heart disease, compared with 10 percent for those who didn’t get dietary advice, researchers found.